In this video you will learn all the science for this topic to get a grade 9 or A* in your science exams!
To cool down, erector muscles relax, so the hairs lie flat, therefore less air is trapped. Sweat glands secrete sweat onto the surface of our skin. The sweat evaporates from our skin into the atmosphere, which increases heat transfer from our body to the atmosphere.
The vessels in our skin dilate, we call this vasodilation. This increases blood flow to skin, so more heat transfers to surroundings.
To warm up, erector muscles contract so the hairs stand up. We don’t produce any sweat from our sweat glands. We shiver, which means our muscle cells contract & relax rapidly, releasing heat via respiration. We undergo vasoconstriction, which means there is less blood flow to our skin, so less heat is transferred to our surroundings.
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